Circuit breaker mechanism with improved mounting arrangement for auxiliary features



CIRCUIT BREAKER MECHANISM WITH IMPROVED MOUNTING ARRANGEMENT FORAUXILIARY FEATURES Filed Sept. 24, 1965 6 Sheets-Sheet 1 June 6, 1967 F.E. MYERS 3,324,264

INVENTOR. FEL/X f. MyE/Pf June 6, 1967 F. E. MYERS 3,324,264

I CIRCUIT BREAKER MECHANISM WITH IMPROVED MOUNTING ARRANGEMENT FORAUXILIARY FEATURES Filed Sept. 24, 1965 6 Sheets-Sheet 2 June 6, E.MYERS CIRCUIT BREAKER MECHANISM WITH IMPROVED MOUNTING ARRANGEMENT FORAUXILIARY FEATURES Filed Sept. 24, 1965 6 Sheets-Sheet 3 INVENTOR. FEA/X4E. M75495 June 6, 1967 F. E. MYERS 3,324,264

CIRCUIT BREAKER MECHANISM WITH IMPROVED MOUNTING ARRANGEMENT FORAUXILIARY FEATURES Filed Sept. 24, 1965 6 Sheets-Sheet 4 1 N VEN TOR.

x, $1 & PEA/X 191/ 414??? June 6, 1967 F. E. MYERS 3,

CIRCUIT BREAKER MECHANISM WITH IMPROVED MOUNTING ARRANGEMENT FORAUXILIARY FEATURES Filed Sept. 24, 1965 6 Sheets-Sheet 5 INVENTOR. FEL/X E. myz/ef June 6, 1967 F. E. MYERS 3,324,254

CIRCUIT BREAKER MECHANISM WITH IMPROVED MOUNTING ARRANGEMENT FORAUXILIARY FEATURES Filed Sept. 24, 1965 6 Sheets-Sheet E United StatesPatent CIRCUIT BREAKER MECHANISM WITH IM- PROVED MOUNTING ARRANGEMENTFOR AUXILIARY FEATURES Felix E. Myers, Haddon Heights, Ni, assignor toI-T-E Circuit Breaker Company, Philadeiphia, Pa, 21 corporation ofPennsylvania Filed Sept. 24, 1965, Ser. No. 490,020 15 Claims. (Cl.200-116) This invention relates to molded case circuit breakers ingeneral and more particularly to an improved structural arrangement foradding auxiliary features thereto in an extremely simplified andexpeditious manner, without costly mechanism changes.

In conventional multi-phase molded case circuit breakers the occurrenceof a fault in any one of the phases will be effective to bring aboutsimultaneous opening of all phases. Typically, a single contactoperating mechanism is provided for all phases and individual faultresponsive means is provided for each phase. All of the fault responsivemeans are effective to operate a common tripper bar, whose operationcauses the operating mechanism to simultaneously open the contacts ofall the phases.

It is oftentimes desirable to bring about opening of the circuit breakerpoles under conditions other than the existence of an over-current faultcondition. For example, it might be desirable to have a shunt tripauxiliary device which will automatically open the circuit breaker unitby the actuation of a push-button, remote from the circuit being sensed.An example of such operation is a machine shop wherein such a remotecontrol push-button will be located in the vicinity of the machine, topermit the operator to automatically interrupt the power input thereto,in the event of an emergency condition.

It is oftentimes also desirable to have an under-voltage type ofauxiliary device :which will open the circuit breaker unit if there isan under-voltage condition. Although fault currents might not begenerated in any one of the individual phases, the equipment might notbe operating in its intended manner, and therefore under suchcircumstances it is best that the operation of the equipment be haltedby a suitable under-voltage trip device.

Another type of auxiliary feature oftentimes required is known as anauxiliary switch. Such a device provides a remote indication of thecircuit breaker condition. Such an auxiliary switch typically containstwo sets of contacts, with a common mid-connector operatively connectedto the associated circuit breaker unit. As the circuit breaker movesbetween its engaged and disengaged conditions, the mid-connector closesor opens respective contact pairs with such information beingtransmitted to a remote location.

In the larger frame size breakers, particularly of the multi-phasevariety, the addition of such auxiliary features is typically achievedby the location of suitable apparatus directly within the units housing.Such arrange ments are typically shown in my US. Patent No. 3,175,064entitled, Shunt Trip and Under-Voltage Device, issued Mar. 23, 1965 aswell as US. patent application Ser. No. 315,312, filed Oct. 10, 1963 inthe name of Carl E. Gryctko, entitled Circuit Breaker Having IsolatedAuxiliary Components, both assigned to the assignee of the inst-antinvention, now US. Patent No. 3,243,563. Such auxiliary devices haveoftentimes been mounted in the very same compartments as the maincurrent carrying elements of the circuit breaker or the operatingmechanism or, as preferably shown in aforementioned US. Patent No.3,243,563, be positioned in separate compartments designated for thereception of the auxiliary devices, and including simplified meansconnected to the tie bar or trip bar of the circuit breaker unit.

In the prior art constructions, it has however been the convenitonalpractice to secure the auxiliary devices to the base of the housing byscrews, bolts or similar conventional fastening means. As circuitbreaker constructions have become more and more compact, it has becomean increasing problem to provide convenient access to the mounting meansfor fastening the auxiliary device to the housing base. Further, theutilization of such prior art fastening means have typically requiredadditional mounting brackets, complementary thereto.

My invention avoids these prior art problems by suitably dimensioningthe axiliary device, such that it snugly enters the base compartment andis closely confined therein for securably maintaining such device in itsdesignated location That is, the auxiliary device of the instantinvention may merely be dropped into the compartment set aside thereforwithout the need for separate fastening means, as had been typicallyrequired in the prior art.

In accordance with preferred embodiments of my invention, which may beof the shunt trip or auxiliary switch variety, the housing base internalcompartment includes a pair of parallel disposed side walls, an endwall, a rear wall, and positioning ribs or recesses. The dimensions ofthe auxiliary device are predeterminedly selected, such that itsimilarly includes a pair of side walls having a spacing approximatingthat of the internal compartment side walls, such that the respectiveside walls closely confront and the end of the auxiliary devicesimilarly confronts the compartment end wall. Also, the auxiliary deviceincludes portions which register with the compartment recesses or ribsfor tightly maintaining the auxiliary device in its desired location.Further, the auxiliary device may also include an upwardly extendingresilient means for abutting the circuit breaker cover and downwardlyurging the auxiliary device in firm seated engagement with the rear wallof its compartment.

As will hereinafter be explained in detail, suitable connections andextensions are provided on the circuit breaker tie bar and common tripbar for operation in conjunction with the auxiliary components, as wellas operation of the circuit breaker unit by the actuation of theauxiliary shunt device.

Accordingly, a primary object of the instant invention is to provide anovel construction for auxiliary features within a circuit breaker unit,which does not require costly or special mechanism changes, and may bemounted to the circuit breaker base in an extremely expeditious manner.

Another object of the instant invention is to provide auxiliary tripdevices for a circuit breaker unit, which may be mounted within thecircuit breaker housing without the need for separate fastening means orassociated brackets.

A further object of the instant invention is to provide auxiliaryfeatures for operation in conjunction with a circuit breaker mechanism,which auxiliary features include devices dimensioned to snugly enter thecompartment of the circuit breaker unit, and are confinedly retainedtherein.

An additional object of the instant invention is to provide such a novelauxiliary device of the shunt trip variety.

Still another object of the instant invention is to provide such a novelauxiliary device of the auxiliary switch variety.

These as well as further objects of the instant invention willbecomereadily apparent after reading the following description of theaccompanying drawings in which:

FIGURE 1 is a plan view of a circuit breaker mechanism, having auxiliarydevices constructed in accordance with the teachings of the instantinvention, and with the cover removed to reveal details thereof.

FIGURES 2, 3 and 4 are cross-sectional views taken along the lines 2-2,33, and 4-4, respectively, of FIGURE 1 and looking in the direction ofthe respective arrows.

FIGURE 5 is a partially exploded perspective view of both a shunt tripand auxiliary switch device constructed in accordance with the instantinvention, and in particular showing the manner in which the auxiliarydevices enter their respective compartments.

FIGURE 6 and 6a are side elevation and plan views respectively of asomewhat modified form of auxiliary switch assembly constructed inaccordance with the novel concepts of the instant invention.

FIGURE 7 is a side elevational view showing another modification of anauxiliary switch device in accordance with the teachings of the instantinvention.

Referring initially to FIGURES 1-5, circuit breaker 10 includes a moldedhousing formed of base section 11 and removable cover 12, held in placeby fasteners 13. Base 11 is provided with end parallel side walls 14 and15, as well as internal partitions 16-19 which ex- .tend parallel toside walls 14, 15 so as to define five parallel discrete compartmentswithin the base 11. In a similar manner cover 12 is provided with sidewalls and partitions which appear as forward extensions of side walls14, 15 and partitions 16-19.

As shown in the circuit breaker frame selected for illustrating theinventive concepts of the instant invention, the outer compartments andthe center compartment each has the current carrying elements and theautomatic trip elements for a single phase of circuit breaker 10. In theensuing discussion, corresponding elements of the various phaseconductive paths and mechanism will be designated by the A, B and Csuffixes, respectively. One of the other compartments has a contactoperating mechanism 20 and the remaining compartment has a plurality ofauxiliary devices which constitute the subject matter of the instantinvention.

A transversely extending common trip bar and tie bar project through allfive compartments for purposes to be hereinafter described. It shouldnaturally be understood that this particular circuit breaker assemblyutilizing the auxiliary devices of the instant invention is forillustrative purposes only and such devices may be used in conjunctionwith numerous other types and sizes of circuit breaker units.

Contact operating mechanism 20 may be any one of trip free mechanismswell known in the art. Reference is however made to FIGURE 2, inparticular, and the description thereof which follows for a cursoryexplanation of operating mechanism 20.

Operating mechanism 20 includes a cradle 21 pivotally mounted at pin 22to mechanism frame 23. Screws 36 received by base inserts 37 fixedlysecure mechanism frame 23 to base 11. An overcenter toggle linkageassembly, including links 26, 27, are joined at the knee pin 28 andconnect cradle 21 to arm 33 at opposed pins 29 and 32, respectively.Clamping member 34 connects arm 33 to the transversely extending tie bar30 at a point remote from pivot pin 32. One end of the pair of operatingsprings 38 is connected to plate 39 pivotally mounted to toggle knee 28.The other end of spring pair 38 is mounted to a web extension 24, whichreceives operating handle 40. Handle 40 extends through cover aperture41 to permit manual operation of the circuit breaker unit.

Latch tip 42 at the left end of cradle 21, as shown in FIGURE 2, isengaged by intermediate latch member 43, which is pivotally mounted toframe 23 at pin 44. Torsion spring 45 mounted to pin 44 biasesintermediate latch member 43 in a clockwise direction, such that itengages extension 46 of common trip bar actuating extension 47, so as tobias common trip bar 25 in a counterclockwise direction. Calibration ofthe operating mechanism is provided by an adjusting screw 48 whichextends through a leg of extension 47 to engage frame cross member 49and thereby limit the counter-clockwise movement and establish thelatching position of trip bar 25.

With trip bar 25 in its most counter-clockwise position, as illustratedin FIGURE 2, latch tip 47a of extension 47 is positioned as to blockcounter-clockwise movement of intermediate latch member 43. However,when trip bar 25 is rotated slightly clockwise from the positionillustrated in FIGURES 2 and 3, latch tip 47a is aligned with aperture43a of latch member 43 so that latch member 43 is no longer restrainedagainst counter-clockwise movement. With member 43 pivotedcounter-clockwise from its position in FIGURE 2, upward movement oflatch tip 42 is no longer blocked and under the urging of operatingsprings 48 upper toggle link pivot 29 will move to the right of the lineof action of springs 38, so that the toggle knee 28 will move to theleft with respect to FIGURE 2. Thus, toggles 26, 27 will collapse,moving pin 32 upwardly and thereby rotating tie bar 30 in acounterclockwise direction with respect to the position shown in FIGURES2 and 3.

The current carrying elements of all three phases A, B and C areidentical, so that only the elements of phase A will be described. Inconjunction therewith, particular reference is now made to FIGURE 3.

With the circuit breaker closed, the current path through phase A is asfollows: Wire grip 51A, terminal strip 52A, stationary contact 53A,movable contact 54A, movable contact arm 55A, flexible braid 56A,L-shaped strap 57A, trip member frame 58A and terminal 59A.

Clamping member 60A fixedly secures member 61A to tie bar 30, with pin62A pivotally mounting contact arm 55A to member 61A. Extension 61A ofmember 61A projects into notch 55 to limit the pivotal movement of arm55A. Compression spring 63 furnishes the pressure to establish goodelectrical contact between cooperating contacts 53A and 54A by bearingagainst arm 55A and member 61A. e

As fully described in US. Patent No, 3,180,953, automatic trip unit 70Ais provided with a delay tripping means in the form of a bimetal 71Afixedly secured at its lower end to one of the legs of member 58A. Theupyer end of bimetal 71A is free to deflect to the right with respect toFIGURE 3, and when sufficiently deflected engages portion 72A of tripbar extension 72A, so as to rotate trip bar 25 in clockwise directionwith respect to FIGURE 3. This serves to cause automatic tripping ofcircuit breaker 10.

Automatic trip unit 70A is also provided, in the conventional manner,with an instantaneous trip means in the form of magnet member 58A andpivoted armature 73A. When the current through member 58A is of asufficient magnitude, the upper end of armature 73A moves to the leftagainst the biasing force of leaf spring 74A and engages leg 72A of tripbar extension 72A, so as to similarly rotate trip bar 25 in theclockwise, or tripping direction.

In a manner well known in the art, contact arms 55B and 55C aresimilarly mounted to transversely extending tie bar 30 in the samemanner previously described for the connection of contact arm 55A.Similarly, common trip bar extensions 72B and 72C (FIG. 1) for theirrespective phases, are provided so as to be engagea-ble by the movingelements of their automatic tripping of all the phases of circuitbreaker 10 should a fault occur in any of the individual phases.

As clearly shown in FIGURES l and 4 and in the exploded view of FIGURE5, the volume between phases B and C, defined by the upstanding sidewalls of partitions 16 and 17, end walls 118 and 119, rear wall 80, andthe top wall of the cover 12, define a discrete compartment 101 forreception of the auxiliary devices, comprising the shunt trip unit andauxiliary switch assembly 110. In

accordance with the novel concepts of the instant invention, theseauxiliary devices are suitably dimensioned to snugly enter thecompartment 101 and be closely confined therein, so as to be firmlyseated and maintained in the auxiliary device compartment, without theutilization of additional fastening means.

Reference is first made to the construction of the shunt trip auxiliarydevice 90. The entire assembly is interconnected to and carried bymagnetic yoke member 92 and bracket member 94. Members 92 and 94 aresuitably interconnected to each other as by welding. Referringparticularly to FIGURES 1 and 5, it is to be noted that the opposedupstanding side walls 91, 93 of yoke member 92 and bracket member 94have a spacing approximating that of internal side Walls 16, 17 of theauxiliary receiving compartment, so as to closely confront thesesidewalls and provide a closely confined fit therebetween. Similarly,rear surface 97 of members 92, 94 are eoplanarly disposed and closelyconfront compartment endwall 119. The bottom leg of bracket member 94includes a downwardly projecting stamped extension 195'which registerswith and enters recess 195 of the compartment rear wall 80, for operablypositioning shunt trip assembly 90 in the designated portion of thehousing compartment. The upper end 95 of retainer bracket 94 resilientlyabuts against the top wall of compartment 101 defined by cover 12 of thecircuit breaker, thereby urging the shunt trip assembly 90 downward,towards the rear wall 80 of circuit breaker base 11.

The trip unit energizing coil 98 is wound about a core plate 100, whichpasses through suitable openings in the arms of magnetic yoke member 92and is staked thereto at 102. A cooperating armature 96 is pivoted toextension 105 of the yoke member, and biased away from the cooperatingpole face of the core plate 100 by spring member 104. The initialarmature gap separation is adjusted by calibration screw member 106,which abuts the upper end of the armature. The calibration setting ismaintained by nut 108 along the shank of screw 106. The leads 107, 109for energizing coil 98 pass through apertures 85 provided withinrecessed portion 84 of the circuit breaker base. When the coil 98 isenergized, armature 96 is attracted to the pole face of core plate 100.This causes armature 96 to pivot clockwise about 105 (as shown in FIGS.4 and 5) such that the upper end of armature 96 moves to the right andin engagement with common trip bar extension 72-AX. This causes aclockwise movement of trip bar 25, thereby tripping all the poles ofcircuit breaker 10.

It should be further recognized that the shunt trip assembly 90 may beconverted to an under-voltage device, merely by undergoing a minormodification thereof. That is, the relationship between the armatureposition and the trip bar extension 72-AX is varied such that theyengage to cause clockwise rotation of tripper bar 25 upon deactivationof the electro-magnetic structure, with the attraction of the armaturetowards the pole face corresponding to the normal condition of thedevice.

Referring now to the auxiliary switch assembly 110, a particularembodiment is shown having two single pole double throw switches 130,132 of the miniature variety and having push-button actuators 131, 133,respectively. It should, however, be understood that only one suchswitch may be used, or more than two switches may be used having othercontact pole ararngements depending upon the requirements of theparticular application and available space within the circuit breakerhousing. Switches 130, 132 are mounted to side plates 112, 114 by aplurality of rivets 116. The lateral spacing between side plates 112,114 approximates that between compartment side walls 16, 17 so as toprovide a closely confronting confined relationship therebetween. Also,forwardly projecting portions 190, 191 of the side support 112, 114,respectively, enter slotted openings 192, 193 Within compartment sidewalls 16, 17. The rear wall of the side supports 112, 114 is disposedimmediately adjacent compartment rear wall 118, and forward wall 197 ofthe side supports 112, 114 is similarly positioned adjacent upwardlyextending housing ribs 196. A spacer member 121 may also be added in anotched region 123 of the side walls so as to further provide a snug fitof the auxiliary switch assembly 110 within its respective compartment.

An actuating arrangement comprising members 140 and operativelyinterconnect the auxiliary switches 130, 132 to the circuit breaker tiebar 30. More specifically, the actuating means includes a first member140, having a generally C-shaped section 142 dimensioned to resilientlysnap'fit about the tie :bar 30 and extending portion 144 which willtravel in a path to abut downwardly turned portion 122 of thecooperating actuating member 120. The condition of FIGURE 4- correspondsto FIGURE 3, wherein the circuit breaker contacts are in the engagedcondition, and tie bar 30 is at its clockwise extreme. Downwardly turnedportion 122 is positioned to translate against actuating button 131 ofauxiliary switch when the actuating member 120 is moved to the left asshown. Actuating member 120 includes another extension 124 whichsimilarly translates against actuating button of auxiliary switch 132.The external circuit connections 81 to the auxiliary switches 130, 13 2pass through base openings 83. When the circuit breaker contacts aremoved to the disengaged condition, either by manual operation or theoperation of one of the phase trip units, the tie bar 30' will bepivoted counter-clockwise such that the upper end 144 of actuatingmember moves to the left, thereby permitting actuating member 120 tomove to the left, so that its downwardly turned extensions 122, 124allow the operating members 131, 133 of the auxiliary switches 130, 132to move outward, to the left, thereby providing a remote indication ofcircuit breaker operation. Adjustment of switch operation may be simplymade by bending of actuator portion 144.

Reference is now made to FIGURES 6 and 6a which show a somewhat modifiedform of an auxiliary switch assembly constructed in accordance with thenovel teachings of the instant invention and wherein corresponding partsare indicated by the same numerical designation. Each of the auxiliaryswitch members 130, 132 has a spring member 160 connected thereto.Spring member 160 includes an actuating portion 164- which will engagetheir respective switch actuator buttons 131, 133, and upwardlyextending resilient portion 163 which engages the cover portion 12 ofthe circuit breaker housing. Actuator portion 164 is located withintransversely extending compartment slots 171, with there being a furtherretaining ear 175 located within spaced housing compartment slots 173for locating the auxiliary switch within the circuit breaker basecompartment 101. Actuation of the auxiliary switches 130, 132,responsive to circuit breaker movement is obtained by a generallyL-shaped actuator member pivoted at 152 to one of the auxilary switchmounting openings. Actuator 150 contains a portion 153 which will beengaged by tie bar 30 upon rotation thereof, such that the upper end 155will be moved to the right, as shown in FIGURE 6, thereby moving slidingmember 170 to the right, so as to move spring portions 164 to the right,and bring about engagement with switch actuator buttons 131, 133.

FIGURE 7 shows a further modification of the general type of auxiliaryswitch assembly shown in FIGURES 6 and 6a, but wherein the actuatormember 150" is direct ly fastened to retainer spring as by welds 157.Actuator member 150' includes a portion 153 which will be engaged by tiebar 30 upon rotation thereof, as well as an opposed portion 155' whichwill move portion 164 of the retainer spring in a direction whichactuates auxiliary switch button 131 upon operation of the circuitbreaker unit. A slidable member, such as shown in FIGURE 6, may be addedto the embodiment shown in FIGURE 7 to provide operation of a pluralityof such auxiliary switch devices.

It is therefore seen that the instant invention provides an improvedstructural arrangement for auxiliary devices used in conjunction withcircuit breaker mechanisms, which auxiliary devices may be added to thecircuit breaker base, without the need for conventional screws, bolts orsimilar fastening means. 7

Although there has been described a preferred embodiment of this novelinvention, many variations and modifications will now be apparent tothose skilled in the art. Therefore, this invention is to be limited,not by the specific disclosure herein, but only by the appending claims.

The embodiments of the invention in which an exclusive privilege orproperty is claimed are defined as follows.

1. A circuit breaker including a housing:

said housing including an internal volume having at least one internalcompartment, including upstanding side walls, an end wall and a rearwall;

said circuit breaker having at least one current conducting mechanism,for carrying a single phase current, said current conducting mechanismincluding a pair of cooperating contacts and an overcurrent responsivetrip unit responsive to a predetermined fault condition of itsrespective phase;

a main operating means operatively connected to said contacts for movingsaid contacts into and out of engagement;

means mounting said current conducting mechanism and main operatingmeans within regions of said internal housing volume external of saidone internal compartment;

an auxiliary operating means being inserted in said one internalcompartment;

said auxiliary operating means responsive to a condition other than asingle phase overcurrent;

mechanical linkage means interconnecting said main and auxiliaryoperating 'means, whereby operation of a predetermined one of saidoperating means causes operation of the other of said operating means;

said auxiliary operating means including at least one auxiliary devicedimensioned to snugly enter said one compartment and be removablyinserted therein;

said auxiliary device including side wall surfaces closely conforming tothe lateral spacing between the upstanding sidewalls of said internalcompartment, such that said sidewalls closely confront said internalcompartment sidewalls and serve to retain said auxiliary device withinsaid one compartment.

2. A circuit breaker as set forth in claim 1.

further including seating means for positioning said auxiliary device ina designated portion of said internal compartment;

said sealing means including a projection carried by said auxiliarydevice, and a complementary opening in said internal compartment forreceiving said projection.

3. A circuit breaker as set forth in claim 1, further including acooperating cover for said housing base;

said cover having a complementary top wall for said one internalcompartment;

said auxiliary device including resilient means for abutting said topwall and rearwardly urging said auxiliary device towards said internalcompartment rear wall.

4. A circuit breaker as set forth in claim 1, including ahousing:

said circuit breaker having at least one current conducting mechanism,for carrying a single phase current, said current conducting mechanismincluding a pair of cooperating contacts and an overcurrent responsivetrip unit responsive to a predetermined fault condition of itsrespective phase;

a transversely extending tie bar operatively connecting said mainoperating mechanism to said current conducting mechanism, whereby thecooperating contacts thereof are operable into and out of engagement bysaid main operating mechanism;

auxiliary device actuating means having a first section engaging aportion of said tie bar extending through said one internal compartment;

said actuating means also having a second section engaging saidauxiliary device for operation thereof responsive to movement of saidtie bar.

5. A circuit breaker as set forth in claim 4, wherein said housingincluding a cover, said cover having a complementary top wall for saidone internal compartment, said auxiliary device including resilientmeans for abutting said top wall and rearwardly urging said auxiliarydevice towards said rear wall.

6. A circuit breaker including a housing:

said housing including at least one internal compartment, includingupstanding side walls, an end wall and a rear wall;

said circuit breaker having at least one current conducting mechanism,for carrying a single phase current, said current conducting mechanismincluding a pair of cooperating contacts and an overcurrent responsivetrip unit responsive to a predetermined fault condition of itsrespective phase;

a main operating mechanism for moving said contacts into and out ofengagement;

a transversely extending trip bar for maintaining said main operatingmechanism in a normal position wherein said operating mechanism iseffective to bring said cooperating contacts into engagement,

means operatively connecting said trip unit to said trip bar, such that,upon the occurrence of an overcurrent fault condition in its respectivephase, said trip unit moves said trip bar to a trip position to releasesaid main operating mechanism and automatically bring said contacts outof engagement;

an auxiliary operating means in said one internal compartment;

said auxiliary operating means responsive to a condition other than asingle phase current;

said auxiliary operating means including an auxiliary device having anactuating portion engageable with a portion of said trip bar extendingthrough said one internal compartment for operating said trip bar tosaid trip position;

said auxiliary device including side wall surfaces closely conforming tothe lateral spacing between the upstanding sidewalls of said internalcompartment, such that said sidewalls closely confront said internalcompartment sidewalls and serve to retain said auxiliary device withinsaid one compartment.

7. A circuit breaker including a housing:

said housing including at least one internal compartment, includingupstanding side walls, an end wall and a rear wall;

said circuit breaker having at least one current conducting mechanism,for carrying a single phase current, said current conducting mechanismincluding a pair of cooperating contacts and an overcurrent responsivetrip unit responsive to a predetermined fault condition of itsrespective phase;

a main operating mechanism;

a transversely extending tie bar operatively connecting said mainoperating mechanism to said current conducting mechanism, whereby thecooperating contacts thereof are operable into and out of engagement bysaid main opera-ting mechanism;

a transversely extending trip bar for maintaining said main operatingmechanism in a normal position, wherein said main operating mechanism iseffective to bring said cooperating contacts into engagement, meansoperatively connecting said trip unit to said trip bar, such that, uponthe occurrence of an overcurrent fault condition in its respectivephase, said trip unitmoves said trip bar to a trip position to releasesaid main operating mechanism and automatically bring said contacts outof engagement;

1 first and second auxiliary devices in said one internal compartment;each responsive to a condition other than a single phase overcurrent;

said first auxiliary device engageable with a portion of said trip barextending through said one internal compartment for operating said tripbar to said trip position;

actuating means having a first section engaging a portion of said tiebar extending through said one internal compartment;

said'actuating means also having a second section engaging said secondauxiliary device for operation thereof responsive to movement of saidtie bar;

f said auxiliary devices dimensioned to snugly enter said onecompartment and be removably inserted therein;

said auxiliary devices including surfaces dimensioned to closelyconfronting said internal compartment walls and maintaining saidauxiliary devices within said one compartment.

8. A circuit breaker as set forth in claim 7, each of 'said auxiliarydevices including a pair of parallel disposed side walls, having aspacing approximating that of said one internal compartment side walls,such that the side walls closely confront, for maintaining said firstand second auxiliary devices within said one compartment.

9. A circuit breaker including a housing, current carrying elementsincluding a pair of cooperating contacts, an overcurrent responsive tripmeans, a main operating mechanism, a first operative connection betweensaid main operating mechanism and contacts for moving said contacts intoand out of engagement, a second auxiliary operating mechanism, anoperative connection between said auxiliary operating mechanism and saidmain operating mechanism whereby operation of a predetermined one ofsaid operating mechanisms brings about operation of the other of saidoperating mechanisms, partition means forming a compartment within saidhousing, means mounting said current carrying elements and said mainoperating mechanism within regions of said housing outside of saidcompartment, said auxiliary operating means including an auxiliarydevice disposed within said compartment, said auxiliary devicedimensioned to snugly enter said compartment and be removably insertedtherein, said auxiliary device including wall surfaces dimensioned toclosely confront the partition walls of said compartment and adapted tomaintain said auxiliary device within said compartment, Without the useof additional fastening means.

10. A multiphase circuit breaker including a housing having meansdefining a plurality of elongated side by side compartments; each phaseof said circuit breaker having current carrying elements including apair of cooperating contacts and an overload trip unit; said currentcarrying elements of a first phase disposed within a first of saidcompartments; said current carrying elements of a second phase disposedwithin a second of said compartments; a main operating mechanism in athird of said compartments; a transversely extending tie bar operativelyconnecting said main operating mechanism to the current carryingelements of said first and said second phases; said tie barsimultaneously transmitting motion from said main operating mechanism tothe cooperating contacts of all of the phases; whereby the cooperatingcontacts thereof are simultaneously operable into and out of engagementby said main operating mechanism; an auxiliary operating mechanismincluding at least one auxiliary device in a fourth of saidcompartments; a mechanical connection between said main and auxiliaryoperating mechanisms whereby operation of a predetermined one of saidoperating mechanisms brings about operation of the other of saidoperating mechanism, said auxiliary device dimensioned to snugly entersaid fourth compartment and be removably inserted therein, saidauxiliary device including Wall surfaces dimensioned to closely confrontthe internal Walls of said fourth compartment and adapted to maintainsaid auxiliary device within said fourth compartment.

11. A multiphase circuit breaker including a housing having meansdefining a plurality of elongated side by side compartments; each phaseof said circuit breaker having current carrying elements including apair of cooperating contacts and an overload trip unit; said currentcarrying elements of a first phase disposed within a first of saidcompartments; said current carrying elements of a second phase disposedWithin a second of said compartments; a main operating mechanism in athird of said compartments; a transversely extending tie bar operativelyconnecting said main operating mechanism to the current carryingelements of said first and said second phases; said tie barsimultaneously transmitting motion from said main operating mechanism tothe cooperating contacts of all of the phases; whereby the cooperatingcontacts thereof are simultaneously operable into and out of engagementby said main operating mechanisms; an auxiliary operating mechanismincluding at least one auxiliary device in a fourth of said compartmentsresponsive to a condition other than a single phase overload, auxiliaryactuating means engaging a portion of said tie bar extending throughsaid fourth compartment; said auxiliary actuating means alsoengaging'said auxiliary device for operation thereof in response tomovement of said tie bar; said auxiliary device dimensioned tosnuglyenter said fourth compartment and be removably inserted therein;said auxiliary device including wall surfaces dimensioned to closelyconfront the internal walls of said fourth compartment, and adapted tomaintain said auxiliary device within said fourth compartment.

12. A multiphase circuit breaker including a housing having meansdefining a plurality of elongated side by side compartments; each phaseof said circuit breaker having current carrying elements including apair of cooperating contacts; said current carrying elements of a firstphase disposed within a first of said compartments; said currentcarrying elements of a second phase disposed within a second of saidcompartments; a main operating mechanism in a third of saidcompartments; a transversely extending tie bar operatively connectingsaid main operating mechanism to the current carrying elements of saidfirst and said second phases; said tie bar simultaneously transmittingmotion from said main operating mechanism to the cooperating contacts ofall of the phases; whereby the cooperating contacts thereof aresimultaneously operable into and out of engagement by said mainoperating mechanism; an auxiliary operating mechanism including at leastone auxiliary device in a fourth of said compartments responsive to acondition other than a single phase overload; each of said individualphase current carrying elements including an automatic overloadresponsive trip unit disposed in the compartment of the respectivephase; a transversely extending trip bar for maintaining said mainoperating mechanism in a reset position wherein said mechanism iseffective to bring said cooperating contacts into engagement; each oftrip units having an actuating portion movable upon the occurrence of afault condition against said trip bar to a trip position to release saidmain operating mechanism and automatically bring said cooperatingcontacts out of engagement; said auxiliary device including an actuatingportion engageable with a portion of said trip bar extending throughsaid fourth compartment for operating said trip bar to said tripposition; said auxiliary device dimensioned to snugly enter said fourthcompartment and be removably inserted therein; said auxiliary deviceincluding Wall surfaces dimensioned to closely confront the internal 1 1walls of said fourth compartment and adapted to maintaining saidauxiliary device within said fourth compartment.

13. A multiphase circuit breaker including a housing having meansdefining a plurality of elongated side by side compartment; each phaseof said circuit breaker having current carrying elements including apair of operating contacts; said current carrying elements of a firstphase disposed within a first of said compartments; said currentcarrying elements of a, second phase disposed within a second of saidcompartments; said current carrying element of a third phase disposedwithin a third of said compartments; a main operating mechanism in afourth of said compartments; a transversely extending tie baroperatively connecting said main operating mechanism to the currentcarrying elements of said first, said second and said third phases; andtie bar simultaneously transmitting motion from said main operatingmechanism to the cooperating contacts of all the phases; whereby thecooperating contacts thereof are simultaneously operable into and out ofengagement by said main operating mechanism; first and second auxiliarydevices in a fifth of said compartments responsive to a condition otherthan a single phase overload; each of said phases having an automaticoverload responsive trip unit disposed in the compartment of therespective phase; a transversely extending trip bar for maintaining saidoperating mechanism in a reset position wherein said mechanism iseffective to bring said cooperating contacts into engagement; each oftrip units having an actuating portion movable, upon the occurrence of afault condition in its respective phase, for said trip bar to a tripposition to release said main operating mechanism and automaticallybring said cooperating contacts out of engagement; said first auxiliarydevice engageable with a portion of said trip bar extending through saidfifth compartment for operating said trip bar to said trip position;actuating means having a first section engaging a portion of said tiebar extending through said fifth compartment, said actuating means alsohaving a second section engaging said second auxiliary device foroperation thereof responsive to movement of said tie bar; said auxiliarydevices dimensioned to snugly enter said fifth compartment and beremovably inserted therein, said auxiliary devices including wallsurfaces dimensioned to closely confront the internal walls of saidfifth compartment and adapted to maintain said auxiliary devices withinsaid fifth compartment.

14. A circuit breaker as set forth in claim 1, wherein said auxiliarydevice and one compartment include cooperating first and second seatingmeans, said auxiliary device carrying one of said seating means, andsaid one compartment including the other of said seating means, saidseating means registering when said auxiliary device is in its desiredlocation within said one compartment, and serving to maintain saidauxiliary device at said desired location.

15. A multiphase circuit breaker as set forth in claim 14, wherein atleast one of said-auxiliary devices and fifth compartment includecooperating first and second seating means, said auxiliary devicecarrying one of said seating means, and said fifth compartment includingthe other of said seating means, said seating means registering whensaid auxiliary device is in its desired location within said fifthcompartment, and serving to maintain said auxiliary device at saiddesired location.

References Cited UNITED STATES PATENTS 2,354,157 7/1944 Swingle 200ll63,171,922 3/1965 Stokes -2 200116 3,204,063 8/1965 Nash et al. 200-1163,243,563 3/1966 Gryctko 200-468 ,BERNARD A. GILHEANY, Primary Examiner.

H. B. GILSON, Assistant Examiner.

1. A CIRCUIT BREAKER INCLUDING A HOUSING: SAID HOUSING INCLUDING ANINTERNAL VOLUME HAVING AT LEAST ONE INTERNAL COMPARTMENT, INCLUDINGUPSTANDING SIDE WALLS, AN END WALL AND A REAR WALL; SAID CIRCUIT BREAKERHAVING AT LEAST ONE CURRENT CONDUCTING MECHANISM, FOR CARRYING A SINGLEPHASE CURRENT, SAID CURRENT CONDUCTING MECHANISM INCLUDING A PAIR OFCOOPERATING CONTACTS AND AN OVERCURRENT RESPONSIVE TRIP UNIT RESPONSIVETO A PREDETERMINED FAULT CONDITION OF ITS RESPECTIVE PHASE; A MAINOPERATING MEANS OPERATIVELY CONNECTED TO SAID CONTACTS FOR MOVING SAIDCONTACTS INTO AND OUT OF ENGAGEMENT; MEANS MOUNTING SAID CURRENTCONDUCTING MECHANISM AND MAIN OPERATING MEANS WITHIN REGIONS OF SAIDINTERNAL HOUSING VOLUME EXTERNAL OF SAID ONE INTERNAL COMPARTMENT; ANAUXILIARY OPERATING MEANS BEING INSERTED IN SAID ONE INTERNALCOMPARTMENT; SAID AUXILIARY OPERATING MEANS RESPONSIVE TO A CONDITIONOTHER THAN A SINGLE PHASE OVERCURRENT;